One-point mooring system for loading or unloading a fluid into or from a ship



June 2, 1970 A. F. DICKSON ETAL 3,515,182

ONE-POINT MOORING SYSTEM FOR LOADING OR UNLOADING A FLUID INTO 0R FROM A SHIP Filed May 5, 1967 2 Sheets-Sheet 1 Ha I8 90 I21: l2

l6 l7 s 5 A WAYAY/AIMYAVAVAKA FIG.I

22 2| Ill 26 25 36 37 28 u u u u N N w W 23 24 NWWW VAWAW/AY AQ I FIG.2

INVENTORS:

ALEXANDER F. DICKSON JOHN G. B. COOMBE FRANCIS 6. WEST THEIR AGENT June 2, 1970 A. F. DICKSON E.TAL 3,515,182

ONE-POINT MOORING SYSTEM FOR LOADING 0R UNLOADING A FLUID INTO OR FROM A SHIP Filed May 5, 1967 2 Sheets-Sheet 3 WVAV/AW A MVMKV/MWVAVAY\MWW I: INVENTORS:

J} ALEXANDER F. 'DICKSON WY/KQmVAWAWWAVAW JOHN COOMBE I54 I FRANCIS 6 WEST FIG.6 Q

THEIR AGENT United States Patent 3,515,182 ONE-POINT MOORIN G SYSTEM FOR LOADING OR UNLOADING A FLUID INTO OR FROM A SHIP Alexander F. Dickson, John G. B. Coombe, and Francis G. West, London, England, assignors to Shell Oil Company, New York, N.Y., a corporation of Delaware Filed May 5, 1967, Ser. No. 636,466 Claims priority, application Great Britain, May 6, 1966, 20,159/ 66 Int. Cl. B65b 1/04 U.S. Cl. 141-387 8 Claims ABSTRACT OF THE DISCLOSURE A one-point mooring system arranged for loading or unloading fluid-cargo ships. The system includes a fixed member anchored to the water floor which carries a rotatable member having a mooring line connected thereto. The fixed member carries a first fluid line which is rotatably connected in fluid communication with a second fluid line carried by the rotatable member. The second fluid line is provided with a swivel to permit swivelling of the second line along a horizontal axis and is attached to a hose connectable to a ship for completing a flow path between the ship and the first fluid line. When the system is not accommodating a ship, the free ends of the hose and mooring line may be attached by means of a cable to a surface buoy to facilitate recovery of the mooring line and hose when the ship approaches.

The invention relates to a one-point mooring system for loading or unloading fluids into or from a ship.

In recent years loading and unloading systems of this kind have been developed comprising a floating buoy to which a ship can be moored in such a way that it can rotate freely around the buoy. Such mooring systems are described, for example, in the U.S. patent to Wassenaar 3,187,355 and U.S. patent to Koppenol 3,261,039 which issued on June 8, 1965 and July 19, 1966, respectively. These known mooring systems, which are being successfully used, are often provided with hoses for loading and unloading which are floating on the surface of the water. A difliculty of these known systems is that when using these systems, a small launch is often needed in order to fasten the mooring cable of the ship and in order to fasten the hose to the ship, which is of course a complication. Furthermore, in calm weather (no wind, waves or currents) the ship tends to bump against the buoy to which it is moored.

The object of the invention is to provide a one-point mooring system for loading and unloading fluids into or from a ship without the above disadvantages.

The system according to the invention therefore comprises a first part and a second part rotatable relative to the first part, the second part being provided with a device for securing a mooring cable of a ship thereto, a first fluid line secured to the first part and a second fluid line rotatably connected to the first fluid line, the system being adapted to be arranged below the surface of a body of water.

Furthermore, the invention comprises a mooring system as mentioned, secured to the bottom of a body of water by anchoring means, the first fluid line being connected to a fluid discharge or supply line arranged in or adjacent to the bottom of a body of water.

The invention will be further explained with reference to the drawings in which:

FIG. 1 is a schematic side veiw of a first embodiment of a mooring system according to the invention, arranged adjacent to and fixedly secured to the bottom of a body of water;

FIG. 2 is a schematic side view, partially in section, of another embodiment of a mooring system according to the invention, also arranged adjacent to and fixedly secured to the bottom of a body of water;

FIG. 3 is a schematic side view of a third embodiment of the invention which is arranged adjacent to and flexibly secured to the bottom of a body of water;

FIG. 4 is a schematic side view of the general arrangement in the water of the system according to the invention, and in particular the manner in which the mooring line and the loading or unloading hose are suspended;

FIG. 5 is a schematic side view of a further embodiment of the invention as arranged underwater; and,

FIG. 6 is a schematic side view of a sixth embodiment of the invention again as arranged under water, fixedly secured to the bottom of a body of water but at a substantial distance above said bottom.

In FIG. 1, a first part 1 is provided with a second part 2, which is rotatable relative to the part 1. Part 1 is flxedly secured by means of flanges 5 and bolts and nuts 6 to a tube pile base 3, which has been drive into the bottom 4 of a body of water. Devices for securing mooring cables of a ship thereto are indicated by 7 and are fixedly secured to the part 2. In the embodiment shown there are two first fluid lines 8 and 8a which pass through and are secured to the first part 1. Second fluid lines 9 and 9a are rotatably connected respectively to the first fluid lines 8 and 8a by a main pipe swivel 10 of the multiple type. The second fluid lines 9 and 9a are each provided with an auxiliary pipe swivel 11 and 11a allowing rotation of part of the second fluid lines 9 and 9a around their longitudinal axes.

The second fluid lines 9 and 9a are supported by the rotatable part 2 by brackets 12 and 12a, which are secured to the part 2, and by hooks 13 and 13a, which are also secured to part 2. The ends of the second fluid lines 9 and 9a are provided with flanges 14 and 14a for connecting hoses thereto, which hoses and their function will be described later. The second fluid lines 9 and 9a are preferably provided with a flexible part, for example, bellows 15 and 15a. To the first fluid lines 8 and 8a are secured fluid discharge and supply lines 16 and 16a, preferably in a flexible manner, for example, by bellows 17 and 17a. On top of the main pipe swivel 10 an eye hook 18 is present for securing the cable of a marking buoy (which will be described later) thereto. The one point mooring system of FIG. 1 is suitable for loading or unloading two different fluids at the same time, namely, the lines 16, 8 and 9 for one fluid and the lines 16a, 8a and 9a for another fluid.

The embodiment according to FIG. 2 comprises a first part 21 and a second part 22 which is rotatable relative to the first part 21. The second part 22 is provided with a device 27 for securing a mooring cable of a ship thereto. The first part 21 is fixedly secured by means of flanges 2S and bolts and nuts 26 to a tube: pile base 23, which has been driven into the bottom 24 of a body of water. A first fluid line 28 is secured to the first part 21. A second fluid line 29 is rotatably secured to the first fluid line 28 by means of a main pipe swivel 30. The end of the second fluid line 29 is provided with a flange 34 for connecting a hose, the purpose of which will be described later, thereto. The second fluid line 29 is preferably provided with a flexible element, for example, a bellows (not shown). A fluid supply and discharge line 36 is secured to the first fluid line 28 by means of a bellows 37. On top of the main pipe swivel 30 an eye hook 38 is provided for securing the cable of a marker buoy (which will be described later) thereto. The basic difference of the embodiment of 3 FIG. 2 with respect to the embodiment of FIG. 1 is that it is suitable only for loading or unloading one fluid.

In FIG. 3, a first part 41 carries a second part 42. The second part 42, which is rotatable relative to the first part 41, is provided with devices 47 for securing a mooring cable of a ship thereto. The first part 41 is fixedly secured, by means of flanges 45 and bolts and nuts 46, to a base 43, which is floating adjacent to the bottom 44 of a body of water 53. The base 43 has the shape of a plate or box and is anchored by means of cables or chains 57 and anchors 59 to the bottom 44. To the first part 41 first fluid lines 48 and 48a are secured. Second fluid lines 49 and 49a are connected to the first fluid lines 48 and 48a by means of a main pipe swivel 50, allowing rotation of these fluid lines relative to each other. The second fluid lines 49 and 49a are each provided with auxiliary pipe swivels 51 and 51a. Furthermore, the second fluid lines 49 and 49a are supported on the second part 42 by brackets 52 and 52a. The ends of the fluid lines 49 and 49a are provided with flanges 54 and 54a for securing a hose (which will be described later) thereto. Preferably each fluid line 49 and 49a is provided with a flexible part, for example, bellows 55 and 55a. Fluid supply and discharge lines 56 and 56a are connected to the first fluid lines 48 and 48a, respectively. On top of the main pipe swivel 50 an eye hook 58 is present to which is secured a cable 60 which is connected to a marker buoy 61 floating on the surface 62 of the body of water 53.

In FIG. 4 the general arrangement in the water of the embodiments according to FIGS. 1, 2 and 3 is schematically shown. Although in FIG. 4 the mooring system shown is secured to a tube pile base, this general arrangement is also applicable to the mooring system according to FIG. 3, which floats adjacent to the bottom of a body of water. Furthermore, although the mooring system as shown in FIG. 4 is one for loading or unloading one fluid only, the general arrangement is equally well applicable to mooring systems for loading or unloading two or more different fluids. In FIG. 4 a first part 71 is fixedly secured by flanges 75 and bolts and nuts (not shown) to a tube pile base 73, which has been driven into the bottom 74 of a body of water 76. A second part 72 rotatable relative to the first part 71 is secured on the first part 71. A first fluid line 78 is secured to the first part 71, said first fluid line 78 being connected in a rotatable manner to a second fluid line 79 by means of a main pipe swivel 80. A fluid supply and discharge line 86, which is arranged adjacent to or in the bottom 74, is connected to the first fluid line 78. The end of the second fluid line 79 is provided with a flange 84 to which is connected a fluid conduit or hose 85. On top of the main pipe swivel 80 an eye hook 88 is arranged, to which is connected a cable 89. To the end of the cable 89 is connected a marker buoy 90, floating on the water surface 81. The second part 72 is provided with a device (not shown) for securing a mooring cable 82 of a ship thereto. The free end of the mooring cable 82 is secured to a buoy 83, floating relatively deep under the water surface 81. The free end 87 of the hose 85 is also secured to the buoy 83, for example, by means of a cable 91. To the buoy 83 a marker buoy 92, floating on the water surface 81, is connected by means of a cable 93. A ship arriving at the mooring system is indicated by the reference numeral 94. The hose 85 is preferably of about neutral buoyancy and is, for example, provided with annular floats 95.

The use of the mooring arrangement as shown in FIG. 4, which applies to all the embodiments according to FIGS. 1, 2, 3, and also of FIGS. and 6, is as follows.

Assume that a ship 94 arrives at the mooring system, in order to load or unload fluid. As soon as the ship 94 has arrived close to the marker buoy 92 it picks up this buoy 92, together with the cable 93, the buoy 83, the cable 91 and the ends of the mooring cable 82 and of the hose 85. In this respect it is remarked that, in order to make the picking up of the buoy 92 easy, this buoy can be provided with a line or rod floating on the water surface, so that the ship can first pick up the said floating rod or line and finally the buoy 92 which is secured to said floating line or rod. The floating rod may be made of fiber glass or of any other suitable material. The end of the mooring cable 82 is then secured to the ship 94 so that the ship 94 is moored. 'Further, the free end 87 of the hose is connected to the fluid loading or unloading pipelines (not shown) on the ship, in any suitable manner. Now loading or unloading of fluid can begin. Assume that it is intended to load the ship 94, which is, for example, a tanker, with oil or natural gas. The fluid to be loaded will then be passed through the fluid supply line 86, the line 78, the main pipe swivel 80, the line 79', the hose 85, the loading lines of the ship 94 into the tanks (not shown) of the ship 94. If it is desired to unload a fluid cargo from the ship 94, the fluid is pumped out of the tanks of the ship through the unloading lines of the ship, the hose 85, the line 79, the main pipe swivel 80, the line 78 and the fluid discharge line 86.

During this loading or unloading of the ship 94, the ship 94 will be free to rotate around, and will always point its bow to the mooring system, since the mooring cable 82 is secured to the second part 72, which is rotatable relative to the fixed part 71 and since the fluid line 79 is free to follow this rotation, because of the main pipe swivel 80 allowing the fluid line 79 to rotate relative to the fixed fluid line 78.

In FIG. 5 a further embodiment of the mooring system according to the invention comprises a first part 101 and a second part 102, rotatable relative to the first part 101. The second part 102 is in the shape of a device, for example, an eye hook, for securing a mooring cable thereto. The first part 101 is fixedly secured to a tube pile base 103 by means of flanges 105 and bolts and nuts (not shown). The tube pile base 103 has been driven into the bottom 104 of a body of water 106'. The first part 101 is provided with a first fluid line 108 which is rotatably connected to a second fluid line 109 by means of a main pipe swivel 110. This main pipe swivel 110 is in the shape of an annular chamber rotatably mounted on the first part 101, the first fluid line 108 passing through the wall of part 101 and debouching into the annular chamber. To the line 109 a hose 107 is secured, the free end 111 of the hose 107 being secured by a cable 112 to a buoy 113, which is floating relatively deep below the surface 114 of the water. A cable 115 for mooring a ship is secured with one end to the second part 102, the other end of cable 115 being secured to the buoy 113. A marker buoy 116 is connected to buoy 113 by a cable 117. Furthermore, a marker buoy 118 is connected to part 102 by a cable 119 and an eye hook 120. A fluid supply and discharge line 121 is connected to line 108 by means of a bellows 122. The hose 107 is provided with floats 123 so that it will have substantially neutral buoyancy.

In FIG. 6, the mooring system comprises a first part 131, fixedly secured to a tube pile base 133 by means of flanges 135 and bolts and nuts (not shown). The tube pile base 133 has been driven into the bottom 134 of a body of water 136. A second part 132, in the shape of an annular ring, is rotatably secured on the first part 131. On the part 132 a device 137 for securing one end of a mooring cable of a ship thereto is present. The other end of the mooring cable 145 is secured to a buoy 143, floating relatively deep under the water surface 144, by means of a cable 142. A first fluid line 138 is secured to the first part 131. This fluid line 138 is rotatably connected to a second fluid line 139 by means of a main pipe swivel 140. To the fluid line 139 is secured with one end a hose 141, which is provided with floats 146, so that it has substantially neutral buoyancy. The other end 147 of the hose 141 is secured to cable 142. A marker buoy 148, floating on the water surface 144, is secured by a cable 149 to tbuoy 143. Another marker buoy 150, floating on the Water surface 144, is secured to part 131 by a cable 151 and eye 152. A liquid supply and discharge line 153 is connected to the first fluid line 138 by means of a bellows 154. The line 153 is arranged adjacent to or in the bottom 134.

The use of the arrangements of FIGS. and 6 is basically the same as the use of the arrangement of FIG. 4, so that further explanation thereof is not considered to be necessary.

The hose (85, 107, 141) can be in the shape of a tube of fiber glass material. Instead, the said hose can also be in the shape of a large number of sections of pipe which are interconnected by universal joints. The said hose has preferably a small negative buoyancy. Furthermore, it is remarked that the said hose can be provided with annular floats in order to give it the desired buoyancy. Instead, it is, however, possible to use a hose which itself is provided with buoyancy cells.

The marker buoy secured to the mooring system by means of a cable and floating above the mooring system can be replaced, if desired, by a mast secured to the mooring system and extending above the water surface.

The one point mooring system according to the invention is suitable for fueling ships with fuel oil or for loading or unloading tankers. All kinds of fluids can be loaded into or unloaded from tankers, by means of the system as described, for example, crude oil, refined products, natural gas, methane, propane or other fluids.

The main pipe swivel can be of the universal type, which means that it allows movement in all directions. Furthermore, all cables used can be replaced by ropes or chains, if desired. The cables can be provided with floats, for example, annular floats.

The system according to the invention can be arranged close to the bottom of the body of water. Instead, it can, however, be arranged at a substantial distance above said bottom (see, for example, FIG. 6).

We claim as our invention:

1. An underwater one point mooring system for loading and unloading fluid-cargo ships, said system comprising:

a first part secured to the floor of a body of water and positioned beneath the surface of said body of Water;

a second part rotatably carried underwater by said first part for rotation about a substantially vertical axis;

a first fluid line secured to said first part;

a second fluid line carried by said second part and having one end rotatably connected in fluid communication with said first fluid line for rotation about said vertical axis;

a pipe swivel connected in said second fluid line to permit swivelling of said second fluid line about a substantially horizontal axis;

flexible fluid conduit means having one end connected to the other end of said second fluid line and having a free end adapted to be connected to a fluid-cargo ship,

buoyant means carried by said fluid conduit means for supporting said fluid conduit means off the floor of the body of water,

buoy means on the surface of said body of water and connected to the free end of said fluid conduit means outboard of said first and second parts whereby said buoy means and said fluid conduit means are free to move in the direction dictated by wind and water forces, and,

at least one mooring line connected to one of said parts and having a free end for mooring said ship to said system.

2. A mooring system as defined in claim 1 wherein said parts are provided with third and fourth fluid lines, respectively, connected in fluid communication with one another and arranged in a manner similar to the connection of said first and second fluid lines.

3. A mooring system as defined in claim 1 wherein said first part is secured to the floor of the body of water by means of anchors.

4. A mooring system as defined in claim 1 wherein said first part is driven into the floor of said body of water.

5. A mooring system as defined in claim 1 wherein said fluid conduit comprises a hose.

6. A mooring system as defined in claim 1 wherein said system is arranged adjacent the floor of said body of water.

7. A mooring system as defined in claim 1 wherein said buoy means comprise at least one surface buoy connected to said free end of said fluid conduit means by cable means.

8. A mooring system as defined in claim 7 wherein said free end of said mooring line is also connected to said buoy means.

References Cited UNITED STATES PATENTS 3,452,787 7/1969 Bily 141388 2,894,268 7/ 1959 Griebe 137-236 3,236,266 2/1966 Bily 137-236 X 3,311,142 3/1967 Bergstrom 141-388 3,372,409 3/1968 Manning 137-236 X HOUSTON S. BELL, J R, Primary Examiner US. Cl. X.R. 13 7-236 

